On Sun, 12 Jan 2014, Alpha Mule wrote:
Hi. AmigaOS 4.x runs natively on some niche PowerPC boards. I was
wondering about the viability of running AmigaOS 4.x on QEMU.
Specifically, I was wondering if there has been any development on
that and/or what needs to be done to get it fully working.
Any information would be appreciated. Thanks.
Looks like not much info is available on this... I think that the first
difficulty is that AmigaOS 4.x is not freely available (AFAIK) so it's
hard to do any testing with it.
I've found that a demo version of MorphOS (which is not the same but
runs on similar hardware) is available and runs on some Mac hardware
that may be closer to what qemu already has support for so it may be an
easier target to test.
I've tried to boot it on qemu but haven't got very far and I think qemu
is missing some features MorphOS needs so it may not be easy to make it
work. Here's what I've found:
1. The CPU type MorphOS seems to prefer is G4 7447A. This CPU type may
not be fully supported by qemu yet and specifying it with -cpu makes the
VM hang in the openbios firmware before it even gets to boot the OS. By
using the default G4 CPU without any -cpu option it gets further and
hangs later in the OS's boot loader.
2. None of the video cards MorphOS can work with is emulated by qemu and
I think those qemu has do not work with MorphOS. So even if it was
running otherwise there would be no display. Theoretically this may be
got around (for testing at least) with the PCI pass-through of an
appropriate card from the host but I don't have such a video card at
hand and don't know if this would be possible in practice at all.
3. The farthest I got is with the 'boot cd:,\mac_ppc32\boot.img' command
line from openbios which seems to at least start to boot but hangs
without any messages (even on the serial console) quite early and I
don't know enough to debug this further. All I got was some debug logs
which seem to go astray around here:
IN:
0x00441b14: dcbtst r8,r10
0x00441b18: stw r5,4(r10)
0x00441b1c: stw r5,8(r10)
0x00441b20: stw r5,12(r10)
0x00441b24: stw r5,16(r10)
0x00441b28: stw r5,20(r10)
0x00441b2c: stw r5,24(r10)
0x00441b30: stw r5,28(r10)
0x00441b34: stwu r5,32(r10)
0x00441b38: bdnz+ 0x441b14
Raise exception at 00441b18 => 00000002 (00)
invalid/unsupported opcode: 00 - 00 - 00 (00000000) 00000080 0
IN:
0x00000034: addi r1,r1,16
0x00000038: lwz r0,52(r1)
0x0000003c: mtlr r0
0x00000040: lwz r0,56(r1)
0x00000044: mtcr r0